System and method for producing pelleted animal feed blocks

ABSTRACT

Animal feed blocks composed of feed pellets are formed by conditioning a meal of a particulated animal feed mixture through heating the meal using steam to cause at least one of the feed components in the feed mixture to bind the meal. The heated meal is mechanically forced through a die to compress the meal into heated pellets. The heated pellets are collected in a pre-formed mold and are compressed in their heated state resulting in the pellets combining to form the animal feed block in the shape of the mold. Systems may use a pellet mill and a hydraulic press where conditioning and pellet formation takes place in the pellet mill and formation of the animal feed block is through compressing a collection of heated pellets using the hydraulic press.

FIELD OF THE INVENTION

The present disclosure relates to systems and methods for producingpelleted animal feed blocks, and to pelleted feed blocks formedtherefrom.

BACKGROUND

Compressed animal feed blocks are generally made using binding agentssuch as chemical additives or lignin-based binders to hold the finalshape of the product. Compressed blocks are also produced by extrudingmaterial into a mold or pressing the extrudate into a mold as a means ofsetting its shape and hardness. Pellet mills typically produce lessgelatinazion of starches and use a combination of mechanical and thermalenergy, as opposed to some extruders that use only mechanical energy.Pellet mills typically only compress particles, whereas extruders maycompress and expand (e.g., through steam expansion of the particles) theparticle. As a result, pellet mills generally soften individualparticles and, in contrast, extruders tend to liquefy the dryingredients due to a combination of high temperature and pressure.However, some binders may not be palatable for the animal consuming thefeed block. In addition, binders may add little or no nutritive value tothe feed block and may add expense to its production.

SUMMARY

In view of the foregoing, systems and methods for producing pelletedfeed blocks are provided in the present disclosure. The feed blocks maybe produced using a pellet mill which may condition the feed materialand form heated pellets, and the heated pellets may be compressed in amold, for example, using a hydraulic press. In some implementations, thecompressed, pelleted feed blocks are formed without using binderadditives.

According to one implementation, a method of preparing a compressed,pelleted animal feed block involves conditioning a meal comprising aparticulated animal feed mixture by heating the meal using steam tocause at least one of the feed components in the feed mixture to bindthe meal and reach a temperature of about 160° F. The heated meal ismechanically forced through a die to compress the meal into heatedpellets having a temperature of at least about 175° F. upon exiting. Theheated pellets are collected in a pre-formed mold and are compressed byexerting a pressure of at least about 90 pounds per square inch whilethe pellets are at a temperature of about 140° F. or higher so that thecompressed heated pellets combine to form the animal feed block.

According to another implementation, a system for forming a compressed,pelleted animal feed block uses a pellet mill to condition a meal formedof a particulated animal feed mixture by injecting steam into the mealto cause particulated animal feed components to bind the meal and bymechanically forcing the conditioned meal through a die to compress themeal into pliable, heated pellets. A mold is used to receive the pelletsand a hydraulic press compresses the heated pellets in the mold byexerting a pressure of at least 90 pounds per square inch while thepellets are at a temperature of at least about 140° F. such that thecompressed heated pellets combine to form the animal feed block. Acontroller controls operating parameters of the system.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a system diagram that may be used in producing feedblocks according to certain implementations.

DETAILED DESCRIPTION

Methods and systems for providing pelleted animal feed blocks areincluded in the present disclosure. Pelleted animal feed blocks may beused as feed supplements or as a complete feed for a variety of animals.For example, the feed blocks may be provided as a supplement to horses,ruminants (e.g., heifers, cows, steer, deer, and goats), sheep, pigs,chicken, and the young counterparts to the aforementioned animals. Inaddition or alternatively, the feed blocks may be provided as a completefeed to chickens, other birds and small mammals such as gerbils andguinea pigs.

Pelleted animal feed blocks may generally be composed of compressed feedpellets formed of meal and may sometimes be referred to as pelletblocks. The meal may be formed of a feed mixture that is ground so thatno whole grains are present resulting in a meal with various particlesizes. The meal may be composed of ground wheat middlings, dehulledsoybean meal, sunflower meal, cottonseed meal, salt, molasses, andmicronutrients (e.g., vitamins and trace minerals) such as calciumcarbonate and mono-dicalcium phosphate, urea and combinations thereof.However, other feed mixtures and feed components may be included in themeal used and the aforementioned examples should not be construed aslimiting.

Nutritionally, the meal may contain fat in an amount up to 10 percent byweight, preferably from about 3 to about 10 percent by weight, or morepreferably from about 3 to about 5 percent by weight of the meal.Protein may be present at about 10 to about 35 percent by weight of themeal, fiber at about 5 to about 15 percent by weight of the meal, andstarch at about 5 to about 15 percent by weight of the meal. Moisture inthe mixture may be present at about 8 to about 13 percent by weight, andpreferably about 8 to about 10 percent by weight of the total weight ofthe meal.

In some implementations, the meal, feed pellets and the compressed feedblock may be free of lignin binders, gums, alginates and othercompositions commonly used as binding agents such as calcium oxide ormagnesium oxide. More specifically, the meal composition itself, e.g.,the protein, starch, fat and/or fiber in the meal may be conditioned soas to bind the composition. Although molasses and other syrup-likecomponents may be included in the compressed feed block, these may serveas a palatant and may be in an insufficient amount to bind the pellets.

Animal feed blocks of the present disclosure are formed generally byproducing a heated meal from a particulated feed mixture; formingheated, compressed pellets from the mash; and re-compressing acollection of pellets into a feed block, e.g., a pellet block.

According to certain implementations, the feed blocks may be produced bythe system depicted in FIG. 1. As shown in FIG. 1, the system 100includes a pellet mill with a conditioner 110 and a pellet die 120, aconveyor 130, scale 140, a pre-formed tub mold 150, a press 160 and acontroller 170. It will be appreciated that other system components maybe included in the system 100 such as a blender for mixing dry feed andheating devices for adding heat to or maintaining the temperature of theheated pellets, and thus the system components depicted in FIG. 1 shouldnot be construed as limiting.

According to certain implementations, the meal is fed into the pelletmill via a feeder, which may control the production rate of the feedblocks. From the feeder, the meal passes into a conditioner 110. In someimplementations, the meal containing the particulated feed mixture maybe blended prior to introduction into the conditioner 110, for exampleusing a 1-ton industrial batch mixer, in order to uniformly distributethe feed mixture components.

In the conditioner 110, the meal is heated with steam to increase itstemperature and add moisture. As heat and moisture are added to the feedmixture, a mash is formed. In particular, steam may be injected into themeal in order to add about 1 percent to about 2 percent by weightmoisture to the mixture. At or prior to the conditioner 110, otherliquid ingredients may be added, such as molasses and sources of fat.During conditioning, the feed composition, such as one or more of theprotein, fat, fiber and starch, may serve to bind the feed components inpellet form. For example, wheat middlings are generally high in starchand during conditioning this starch may gelatinize and bind the feedcomposition. In another example, cottonseed meal cake includes fiber andprotein, and one more of these components may serve to bind the feedcomponents. In particular, cottonseed meal is a binder and may serve tobind the animal feed block. Accordingly, the pellets and the compressedfeed block may be free of binders such as lignin binders as themanufacturing process described herein causes one or more of the feedmixture components in the meal to serve as a binder.

Upon exiting the conditioner 110 of the pellet mill, the heated meal isintroduced into the pellet mill die 120 where it is compressed throughthe holes defined by the die. During this compression, the meal isheated further due to friction and the added mechanical energy. Forexample, a temperature increase associated with mechanical energy andfriction in the meal may add about 5 to 25° F. of thermal energy. Theconditioned feed mixture exits the die in a ribbon that may be slicedtransversely to form pellets. Once the pellets have exited the die 120,they are hot and have a pliable texture and the meal is bound togetherin a compressed, pellet-form as a result of the conditioning andmechanical force through the die 120. In some implementations, theheated pellets may exit the die at temperatures between 160° F. and 190°F., and preferably between about 170° F. to 180° F., or at least about170° F.

During pelleting, and as provided above, the fat content in the meal ormash is generally 10 percent by weight or lower, preferably from about 1to about 10 percent by weight, or more preferably from about 3 to about5 percent by weight of the mixture. These lower levels of fat enable thedie to maintain a level of mechanical energy and friction on the mealthat allows it to compress and soften. Otherwise, higher levels of fatduring pelleting will reduce the friction mechanical energy preventingthe meal from compressing and softening and instead would travel throughthe die rapidly and with insufficient energy absorbed.

Accordingly, the pellet mill adds heat and moisture from the conditioner110 to soften and cause binding of the feed material, and usingmechanical energy from compression through the die 120, the meal isfurther heated and softened, thereby providing a pliable pellet. Thecompositional profile of the feed pellets exiting the die 120 issubstantially the same as the composition of the meal entering thepellet mill with the exception that about 1 to 2 percent moisture byweight of the pellet is added. In particular, components such asmoisture and fats in the form of oil are not lost during processing inthe pellet mill. After movement through the die 120, the hot pellets maybe collected at the exit of the pellet mill door.

Although a pellet mill is contemplated as the preferred device forconditioning the mash and forming heated pellets in the presentdisclosure, other devices adapted to condition the feed mixture are alsowithin the scope of the present disclosure, and conditioning using apellet mill should not be construed as limiting.

The finished pellets may have a diameter of ⅛″ to ¾″ or preferably about11/64″; may have a length of from about 1/16 to about 3″; and may beprovided in a variety of shapes and sizes, such as in cylindrical orcube shapes. The pellets may weigh from about 0.04 grams to about 40grams each. For example, ¾″ diameter range cubes may weigh 20 to 35grams each, depending on the length. 11/64″ pellets may weigh from about0.25 grams to about 0.35 grams each depending on length. ⅛″ pelletsweigh from about 0.08 to about 0.10 grams each depending on length. Thepellets may contain up to 9 to 14 percent moisture by weight of thepellet, and preferably about 10 to 13 percent moisture by weight, orabout 12 percent moisture by weight.

The finished pellets may be placed in a holding vessel or directly intoa tub mold 150 in their heated state. For example, a belt conveyor 130may move the hot pellets to a holding container for subsequentseparation in a tub mold 150, or the conveyor may deposit the hotpellets directly into the tub mold 150. Alternatively, the pellets maybe manually added to these vessels. The total weight of the pelletsadded to the tub mold 150 is measured using a scale 140. A metal ringmay be placed on the top edge of the mold, for example, to extend thevolume of the mold and thus its capacity for holding a desired weight ofpellets. In certain implementations, feed components may be combinedwith the pellets in the tub mold 150 prior to pressing. For example,grains such as cracked grains (e.g., cracked corn) oats and other feedcomponents not having passed through the pellet mill may be added to thecollected pellets.

The mold 150 and the optional ring filled with pellets may be placed ina hydraulic press 160 where pressure may be applied from the top of themold onto the pellets as the pellets are compressed into a mass in theshape of the mold 150. The hydraulic press typically holds the heatedpellets under compression at about 90 to about 240 psi and preferably atleast at 130 psi for a holding period from about 1 to about 15 minutesdepending on the desired final hardness of the pellet block. Inparticular, a lower holding time will result in a softer pellet blockand a longer holding time will produce a harder pellet block due to thesustained pressure facilitates the pellets binding to each other.Accordingly, during the holding period the soft pellets may becompressed together and may combine such that the mass of pellets takethe shape of the mold 150. The collection of pellets may be held underpressure for several minutes while combined mass begins to cool andtherefore hold the shape of the mold. As the pressure and hold timeinterval are increased, the product tends to become harder. In someimplementations, the compositional profile of the feed blocks producedfrom the mold 150 is substantially the same as the composition of theheated pellets exiting the pellet mill. In particular, during pressing,moisture is not lost as a result of compressing the heated pelletstogether in the mold 150 and thus a moisture level of the feed block issubstantially the same as a moisture level of the heated pellets.

It has been discovered that the feed pellets in their compressed, heatedstate are particularly suited for use in forming feed blocks. While feedpellets are typically cooled immediately after exiting a pellet mill,the implementations of the present disclosure use the pellets in theirheated state to form feed blocks. Further, the implementations of thepresent disclosure are in contrast to other approaches that form feedblocks from heated meal. The compressed meal in pellet form and thethermal energy within the pellets facilitates bonding of the feedpellets to form the feed block. Moreover, methods and systems of thepresent disclosure form the feed blocks in such a way that thecomposition of the meal is retained through the formation of the heatedpellets and the subsequent feed blocks. This is in contrast toapproaches where oils or moisture are removed during production. Becausepellets are more dense than meal, pellets can be more readily packedinto the mold. The additional pressure from the hydraulic pressincreases the hardness of the pellets in the block beyond the hardnessof the pellets alone.

According to certain implementations, from the time the heated pelletsexit the die 120 to the time the heated pellets are pressed in thehydraulic press 160, the pellets are not cooled using a cooling deviceand moisture is not removed from the pellets. Consequently, thetemperature of the pellets remains similar to the pellets exiting fromthe pellet mill die. By maintaining the pellets at elevatedtemperatures, subsequent pressing in the hydraulic press enables thepellets to combine into a pellet block without the use of additionalbinders. Preferably, the temperature of the collected pellets in thevessel remains between about 140° F. to about 160° F. until pressing. Insome implementations, the heated pellets in the mold 150 or other vesselmay be covered to retain heat. In addition or alternatively, the heatedpellets may be rapidly moved from the pellet mill to the hydraulicpress, such as via a conveyor, or may be exposed to an external heatsource so that the temperature of the heated pellets remains at leastabout 140° F. prior to using the hydraulic press 160.

The production of the compressed, pellet blocks may be controlled usinga controller 170 configured to control the operating parameters of thedevices of the system 100 such as the pellet mill, the hydraulic pressor presses, conveyors, scales and external heat sources, if present. Insome implementations, the controller may be configured as a computer, asa control panel or a combination of these.

In some systems, multiple presses may be operating simultaneouslybecause the heated pellet production rate from the pellet mill mayexceed the production rate of the pellet blocks using a single press.For example, where the pellets are produced at a rate of about 1.5 tonsper hour and thus 50 lbs. of heated pellets can be collected per minute,and where a 10 to 250 pound pellet block is formed after a holding timeof about least 5 minutes, multiple presses may be provided so that theheated pellets are not held for a time where pellets cool below 140° F.However, where production rates are slow or where the heated pelletswould otherwise cool below desired temperatures, the pellets may beheated using external heat sources in order to maintain the temperatureand moisture content of the pellets at a level that is substantiallysimilar to the temperature and moisture content as the pellets directlyupon exiting the conditioner.

EXAMPLES

It has been discovered that the temperature of the heated pellets at thetime of pressing, the hold time during pressing, pressure of thehydraulic press and the formulation of the feed block may all have aneffect on the final hardness of the blocks. Accordingly, the followingthree examples illustrate trials where compressed feed blocks wereproduced from heated pellets. These examples are provided by way ofillustration and should not be construed as limiting, as those skilledin the art will appreciate various modifications of the present examplesfall within the spirit and scope of the present disclosure.

Example 1

An investigation was conducted to determine whether heated pellets freeof binders and formed from a pellet mill could be compressed into asolid block with an acceptable hardness, such as a block with a hardnessof at least 45 psi when tested using a pneumatic tester having a ⅜″diameter pin being driven ½″ into the top surface of the block.

Materials and Methods:

The compositions listed in Table 1 below were mixed in a 1-ton batchmixer to form a meal. The blended meal was subjected to conditioning inpellet mill and run across the 11/64″ die with a target conditioned mealtemperature of 170° F. at a feed rate of 50 pounds per minute, with thepellet mill motor requiring 36 amps. The base meal temperature was 76°F., the conditioned meal temperature was 171° F. and the hot pellettemperature was 190° F. upon exiting the pellet mill.

Pellets were collected as they exited the pellet mill door and placed ina large plastic tub. The filled tub was covered to maintain thetemperature of the pellets at approximately 180° F. and the tub wasmoved to a 50-ton hydraulic press. 55-pounds of the pellets were placedin a smaller tub and placed in the press, and the desired pressure wasapplied and held for the hold time. The first two tubs were made usingthe hydraulic press at a maximum pressure of 93 psi, and the press wasadjusted to 127 psi for the remaining tubs. It was noted that minimalamounts of product was squeezed out around the edges of the press headand moisture from the mash was retained within the tub.

After 24 hours, the tubs were tested for hardness with the pneumaticblock tester using the ⅜″ diameter pin and driving it into the topsurface of the block to a depth of ½″ and recording the amount of airpressure that was required. After hardness testing, one of the blockswas core drilled and the material was tested for its water activity asan indication of potential mold growth.

TABLE 1 WHEAT MIDDLINGS 61.47 DEHULLED SOYMEAL 9.60 SUNFLOWER ML (DH)15.50 CALCIUM CARBONATE 1.59 MONO-DICAL PHOSPHATE 0.29 SALT 0.55 UREA3.50 VEGETABLE FAT 2.50 MOLASSES 5.0 SUB-TOTAL 100.000

Results and Summary:

TABLE 2 Pelleted Feed Tub Hardness Results Press Pressure Hold TimeHardness (psi)  91 psi 5 minutes 46  91 psi 5 minutes 53.5 127 psi 5minutes 70 127 psi 7.5 minutes 67 127 psi 10 minutes 52

From the hardness data of Table 2, it appeared counter-intuitive thatthe hardness of the 127 psi pressure treatments was actually reduced asthe hold time increased. However, the pellets were collected in onelarge tub and then divided into 55-pound portions in a smaller tub, insequence, for pressing. This meant the first block pressed at a 5-minutehold time had the hottest temperature compared to the 7.5- and 10-minutehold times. The lag time between pellet formation and pressing allowedthe pellets to cool and start to harden prior to being pressed. Forexample, while the hot pellet temperature was 190° F. upon exiting thepellet mill, after 15 minutes in ambient temperatures, the hot pelletscooled to 140° F. This would seem to indicate that minimal hold timebetween the pellet mill and the press is desired.

In general, the increased pressure from 91 to 127 psi increased thefinal hardness of the blocks and higher press pressures should result ineven harder blocks.

A concern with this process is also that there may be mold growth sincethe moisture added at the conditioner prior to the pellet mill was notremoved by a cooler. Water activity of the finished tub was measured at0.71. This water activity level may be reduced by providing a lowermoisture steam to condition the meal and by adding salts to the baseformula. In further implementations, salt, antimicrobials (e.g., 0.5percent by weight propionic acid) or both may be added to the pelletformula to reduce water activity below a level that sustains moldgrowth.

Example 2

In this example, further investigation of compressing heated pelletsfree of binders into a tub involved studying the effect of fat on thefinal hardness and the feasibility of producing feed tubs formedprimarily of cottonseed meal.

Materials and Methods:

The compositions listed in Table 3 below were mixed in a 1-ton batchmixer to form a meal of particulated feed. The blended meal wassubjected to conditioning in pellet mill and run across the 11/64″ diewith a target conditioned meal temperature of 180° F. to 185° F. at afeed rate of 100 pounds per minute. These conditions were held constantfor the first three formulas. As the fat content increased in the firstthree compositions, the level electricity required to run the pelletmill decreased from 45 amps at 5 percent by weight fat to 32 amps at 9percent by weight fat. For the two cottonseed meal treatments, the 11/64pellet was run at 180° F. and the pellet mill required 70 to 80 amps.When this same formula was run on the ¾″ cube die, the conditioned mealtemperature was only able to get to 160° F. and pulled between 50 and 60amps.

Pellets were collected as they exited the pellet mill door and placed ina large plastic tub. The filled tub was covered in order to maintain thetemperature of the pellets at approximately 180° F. and the tub wasmoved to a 50-ton hydraulic press. 55-pounds of the pellets were addedto a smaller tub, the tub was placed in the press and the desiredpressure was applied and held for the hold time. The tubs were pressedwith 127 psi and held for 8 minutes. It was noted that minimal amountsof product were squeezed out around the edges of the press head andmoisture from the mash was retained within the tub.

TABLE 3 RATION RATION RATION RATION 4 1 2 3 COTTON 5% FAT 7% FAT 9% FATCAKE MAIN FORMULA CALCIUM CHLORIDE 1.00 WHEAT MIDDLINGS 62.03 60.0358.03 COTTONSEED MEAL 89.50 DEHULLED SOYMEAL 9.60 9.60 9.60 SUNFLOWER ML(DH) 15.50 15.50 15.50 CALCIUM 1.58 1.58 1.58 CARBONATE MONO-DICAL 0.290.29 0.29 PHOSPHATE SALT 1.00 1.00 1.00 UREA 3.50 3.50 3.50 VEGETABLEFAT 2.5 4.50 6.50 3.00 MOLASSES 4.00 4.00 4.00 3.00 CALCIUM CHLORIDE3.50 SUB-TOTAL 100.000 100.000 100.000 100.000

After 24 hours, the tubs were tested for hardness with a pneumatic blocktester using a 3/16″ diameter pin. Testing involved using air pressureto drive the pin into the top surface of the block to a depth of ½″ andthe amount of air pressure required was recorded.

Results and Summary:

The hardness results using the pneumatic tester are provided in Table 4below.

TABLE 4 Tub 1 Tub 2 Product Pressure (psi) Pressure (psi) Ration 1 - 5%Fat 11/64″ Pellet 38 32.6 Ration 2 - 7% Fat 11/64″ Pellet 30.6 28.3Ration 3 - 9% Fat 11/64″ Pellet 23 26.3 Ration 4 - CSM 11/64″ Pellet 5652 Ration 4 - CSM ¾″ cube 72.3 58.6/58.6

As the level of fat in the mash and resulting feed block increased inthe formula, the hardness tended to decrease as expected. The cottonseedmeal treatments were made with a common formula as provided in Table 4.The larger size of the cube (¾″) being pressed into the tubs tended tomake a harder product than when a smaller pellet ( 11/64″) was used. Thelarger cubes may have retained heat from conditioning better providingmore pliability when pressed, and may have resulted in a harder finishedproduct. In addition, calcium chloride was added to the cottonseed mealformula and likely had a positive effect on the hardness of the finishedproduct.

Example 3

This study looked at three aspects of the processes for producingcompressed, pelleted feed blocks: 1) the effect of adding a ligninbinder to the base formula; 2) adding grains to the hot pellets prior topressing; and 3) looking at the effect of the pelleting compared to onlysteam conditioning the base formula.

Materials and Methods:

The compositions listed in Table 5 were mixed in a 1-ton batch mixer,and the meal was delivered to a pellet mill and run across a 11/64″ diewith a target conditioned meal temperature of 160° F. and a feed rate of80 pounds/minute. Pellets were collected upon exiting the pellet milldoor and placed in a plastic tub. A cardboard cover was placed on top ofthe pellets to try and retain their temperature. The plastic tubs werethen moved to the first floor where the press was located.

For the tubs that had the cracked corn and oats added, the pellets wereweighed out to the correct amount, then the pre-weighed corn and oatswere added. The pellets and grains were then blended by hand in the tub.

Each tub was placed in a 50-ton press and the desired pressure wasapplied and held for the hold time. The pellets or mash were thensubjected to 127 psi using the hydraulic press for hold times of either5 or 10 minutes. It was again noted that minimal amounts of product wassqueezed out around the edges of the press head.

After 4 days, the tubs were tested for hardness with the pneumatic blocktester using the 3/16″ diameter pin and driving it into the top surfaceof the block to a depth of ½″ and recording the amount of air pressurethat was required.

The pellet mill operating amperage, mixed meal temperature, conditionedmeal temperature, hot pellet temperature and hardness values areprovided in Table 6.

TABLE 5 Control Binder ALFALFA LEAF MEAL 4.00 4.00 WHEAT MIDDLINGS 13.0112.01 DEHULLED SOYMEAL 61.61 61.61 LIGNIN BINDER 0.00 1.00 CALCIUMCARBONATE 6.14 6.14 MONO-DICAL PHOSPHATE 4.96 4.96 SALT 1.00 1.00MOLASSES 4.00 4.00 SOY OIL-CRUDE 4.00 4.00 MAGNESIUM OXIDE 51 1.28 1.28SUB-TOTAL 100.00 100.00

TABLE 6 Pellet Mixed Cond. Hot Run Mill Meal Meal Pellet Hardness No.Variable Amps Temp° F. Temp° F. Temp° F. psi 1 Control-Pellet-5 minute38 84 161 170 71 2 Control-Meal-5 minute 31 84 162 160 66 3Control-Pellet-10 minute 37 84 162 172 82 4 Control-meal-10 minute 30 84161 157 73 5 Control-Pellet + corn and Oats-5 minute 35 84 162 175 37 6Control-Pellet + corn and Oats-5 minute 36 84 161 173 43 7Lignin-Pellet-5 minute 36 84 161 172 83 8 Lignin-Meal-5 minute 30 84 161153 68 9 Lignin-Pellet-10 minute 35 84 161 176 88 10 Lignin-Meal-10minute 30 84 160 151 77 11 Lignin-Pellet + Corn and Oats-10 minute* n/an/a n/a n/a 76 12 Lignin-Pellet + Corn and Oats-10 minute* n/a n/a n/an/a 48 *Operating conditions were not recorded

Results and Summary:

The first comparison between runs 1-6 and 7-12 studied whether adding alignin binder would increase the hardness of the final tubs. Whenlooking at treatments with similar hold times, the addition of thelignin binder did slightly increase the hardness of the products in eachcomparison. For example, the pellets that were held for 5 minutesincreased from a hardness of 71 to 83 with the addition of the lignin.Also, with the meal held for 10 minutes, the hardness increased from 73to 77 with the addition of the lignin binder to the formula. However,the hardness of the control pellet in runs 1-6 were sufficiently hardfor purposes of transport and limiting ingestion by the animal.

The second comparison between pelleted and meal runs either held for 5or 10 minutes, e.g., comparisons between runs 1 and 2, 3 and 4, 7 and 8and 9 and 10, studied whether the hardness of the pellet block increasedwhen the product was run across the pellet die in addition to beingsteam heated in the conditioner compared to only being run through theconditioning chamber and by-passing the pellet die. In all comparisonsprocessing the meal across the pellet die increased the hardness of thefinal product. For example, the control meal pressed for 5 minutesincreased from 66 to 71 when it was pelleted. Also, in the lignin 10minute hold time variables, the hardness increased from 77 to 88 whenthe product was processed across the die.

The final comparison investigated whether the addition of cracked cornand whole oats in runs 5, 6, 11 and 12 was feasible in thismanufacturing method. In both products that were produced, i.e., thecontrol and lignin formulas, the addition of the cracked corn and oatsmade an acceptable looking product with good distribution even thoughthe hardness of the product was reduced. The reduction in hardness mayhave resulted from three different sources of variation. First, when thecorn and oats were mixed with the hot pellets, the time betweencollecting the pellets and pressing the tub increased. In Example 1, itwas noted that this lag time tended to reduce the hardness of the tubs.The second source was likely the addition of the corn and oats, whichwere at ambient temperatures at the time of addition. As a result, thislikely reduced the overall temperature of the product, i.e., bydilution. Lastly, the corn and oat particles may have reduced the totalamount of binding area within the finished tub and thus reduced thefinal hardness.

For the control treatment where the cracked corn and whole oats wereadded, i.e., in runs 5 and 6, the hot pellets made up 70 percent byweight of the composition, the cracked corn made up 20 percent byweight, and the whole oats were included at 10 percent by weight. Thesetubs were offered to horses where the pellet blocks were readilyconsumed. It was noted that the horses could scrape the product withtheir teeth and separate the pellets out an then consume them.

For lignin treatments where the cracked corn and whole oats were added,i.e., in runs 11 and 12, the hot pellet made up 85 percent by weight ofthe ration, the cracked corn was 10 percent by weight, and the wholeoats 5 percent by weight. These tubs were sent offered to ruminants andwere readily consumed.

The compositions, apparatuses and functions of the variousimplementations may be used interchangeably to form alternativeimplementations, as would be appreciated by those skilled in the art.Although the present disclosure provides references to preferredembodiments, persons skilled in the art will recognize that changes maybe made in form and detail without departing from the spirit and scopeof the invention.

What is claimed is:
 1. A method of preparing a pelleted animal feedblock comprising: conditioning a meal comprising ground animal feedcomponents by heating the meal using steam to cause at least one of thefeed components to bind the meal and reach a temperature of about 160°F.; mechanically forcing the heated meal through a die to compress theconditioned meal into heated pellets, wherein the heated pellets exitthe die at a temperature of at least about 175° F.; collecting theheated pellets in a mold; and compressing the heated pellets in the moldby exerting a pressure of at least about 90 pounds per square inch up toabout 240 pounds per square inch for about 1 minute up to about 15minutes with the pellets at a temperature of about 140° F. or highersuch that the compressed heated pellets combine to form the pelletedanimal feed block comprised of compressed pellets having a hardness thatis greater than a hardness of uncompressed pellets after cooling,wherein the temperature of the pellets is maintained at about 140° F. orhigher upon exiting the die until compressing.
 2. The method of claim 1,wherein the pelleted animal feed block has a hardness of about 40 psi toabout 80 psi using a pneumatic tester with a 3/16″ diameter pin anddriving the pin into a top surface of the block to a depth of ½″.
 3. Themethod of claim 1, further comprising subjecting the heated pellets toheat retention methods after exiting the die until collecting the heatedpellets in the mold.
 4. The method of claim 3, wherein the heatretention methods are selected from the group consisting of covering thepellets, rapidly moving the pellets from the die to the mold, andexposing the pellets to an external heat source.
 5. The method of claim1, wherein the heated pellets exit the die at a temperature of up toabout 190° F.
 6. The method of claim 1, wherein the heated pellets exitthe die at a temperature of up to about 180° F.
 7. The method of claim1, wherein the steam is injected steam and adds about 1 to about 2percent moisture by weight of the meal.
 8. The method of claim 7,wherein the meal includes a moisture content of about 8 to about 10percent by weight of the meal and the feed block includes a moisturecontent of about 9 to about 12 percent by weight of the feed block. 9.The method of claim 1, wherein the meal comprises up to about 10 percentfat by weight of the meal.
 10. The method of claim 1, wherein the mealcomprises one or more of starch, fat, proteins or fiber, and wherein oneor more of the starch, fat, proteins or fiber bind the meal duringconditioning such that the heated pellets are formed from theconditioned animal feed mixture.
 11. The method of claim 1, wherein amoisture level of the pelleted animal feed block is substantially thesame as a moisture level of the heated pellets.
 12. The method of claim1, wherein the heated pellets and the pelleted animal feed block arefree of added lignin binders.